Around 1,000 people, including many Christians, are expected to rally outside Parliament today in opposition to the Government's plans to allow research on human-animal "hybrid" embryos.

The Time to Stand rally is the first in a series of rallies planned by Christian Concern For Our Nation (CCFON) in protest of the Human Fertilisation and Embryology Bill, which the Lords will be voting on later on Tuesday.

If passed, the Bill will enable scientists to experiment on a whole range of human-animal hybrids, including "cytoplasmic" embryos, which are 99.9 per cent human and involve inserting human cells into an animal egg, and "true" hybrids, which are created by mixing human sperm with an animal egg or vice versa.

Today's rally is also in protest of provisions under the Bill for embryos to be selected as a 'saviour sibling' while the remaining embryos are discarded, and to remove the need for a father for children created by IVF.

CCFON's Andrea Minichiello Williams urged Christians to pray that "God's creation is not marred by this Bill and that the sanctity of human life is preserved".

Meanwhile, in a pastoral letter sent to all 500 Catholic parishes in Scotland this week, the Bishops' Conference of Scotland has urged the Government to allow a free vote in Parliament on the Human Fertilisation and Embryology Bill.

In the letter, written by the President of the Joint Bio-ethics Committee Archbishop Mario Conti, the bishops recognise the "right and duty (of MPs) to vote in such issues according to conscience" and point out that many other countries have "drawn the line at human cloning", though regrettably the UK Government has not.

Quoting from a statement by the Pontifical Academy for Life, the Bishops describe, the fusion of animal and human material resulting in hybrid embryos as a "monstrous act against human dignity".